Thomas l



(No Hedel.)

T. L. RANKIN.

10B MACHINE.

No. 244,300. Patented July 12,1881;

,AT-mem. INVENTU-n.:

NA FEIERS. Pbolo-Lumgnphnr. waminmum n. C.

UNITED STATES PATENT .OFFICEo THOMAS L. RANKIN, OF NEW YORK, N. Y., ASOSIGNOR TO THE RANKIN ICE MANUFACTURING COMPANY, OF SAME PLACE.

ICE-MACHINE.

SPECIFICATION forming part of Letters Patent No. 244,300, dated July 12, 1881.

Application filed May 5,1881. (No model.)

To all whom it may concern:

Be it known that I, THOMAS L. RANKIN, of New York, in the county and State of New York, have invented certain new and useful 5 Improvements in Ice-Machines; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, and to the letters of reference marked thereon, which 1o form part of this speciiication.

This invention relates to means for feeding a refrigerating liquid to the stacks of pipes which are arranged between the pairs of freezing-plates in an ice-machine, and to means for i5 loosening the blocks of ice from the freezingplates, in order that they may be removed after bein g formed. These stacks are arranged vertically, and it has been customary to pass the refrigeratin g liquid through them from the top 2o downward and off to the condensing apparatus. As the liquid or gas passes downward through the successive coils of the stack its temperature is gradually raised to that of the water in the chambers inclosed by the freez- 25 ing-plates, so that the water is not congealed uniformly, but the blocks of ice formed therefrom are solidly frozen the full width of the chamber at the top, and decrease in thickness downward. To remedy this defect I have pro- 3o vided areversiblefeeding apparatus by means of which the refrigerating material is caused to ilow alternately upward and downward through the stacks of pipes, so that the freezing proceeds uniformly throughout the water 3 5 chambers or tanks, and blocks of ice of uniform thickness are formed. The ice adheres closely to the plates between which it is frozen, and heretofore, in order to loosen it, the ilow of freezing material, such as liquefied ammo- 4o nia-gas, has been stopped in the pipes, only a sufficient quantity being left therein to expand into gas, which, after its expansion, has a higher temperature and thaws the surface of the ice from the plates. This method, as is 4 5 obvious, retards the operation of the machine and reduces its capacity, while the thawing is taking place, as the weak water has to be cooled in order to reabsorb the gas. To overa come this objection I simply cut off the iow of liqueed ammonia and pass a small stream 5o of the weak water of ammonia through the stack of pipes between the plates from which the ice is to be removed, which has the eifect of raising their temperature and loosening the ice. This weak water in passing off meets the 5 5 gas from the other stacks in the common pipe which conducts the gas from all back to the absorber, and absorbs a portion of it, thus facilitating the subsequent absorption process,

so that a real benefit to the operation of the 6o machine is thus made an incident of the thawing-oft' process.

In the accompanying drawings, Figure 1 is a verticalV section of a portion of an ice-inachine, showing the stack of pipes arranged in 65 connection with the supply and eduction pipes. Fig. 2 is a partial perspective view of the machine.

The letter A designates the stack of circulatingpipes which is arranged between the 7o freezing-plates B B, its upper terminalbeing connected to a pipe, O, and its lower terminal to a pipe, C', these pipes in my invention being alternately supply and eduction pipes, the pipe O being connected by a pipe, D, with a 75 pipe, E, which connects with another pipe, F, arranged to connect with the absorber, which is not shown in the drawings. The pipe C is also connected by a pipe, G, with a pipe, H, arranged to connect with the reservoir of the 8o weak'water of ammonia, which, also, is not shown in the drawings. The pipe C is connected by a pipe, l, with a pipe, E', connecting with the pipe F. The pipes O and C are connected, respectively, with pipes K and K', 85 which connect with a pipe, L, for conducting the expanded gas back to the condensing apparatus.

The operation as now shown and described for one stack of pipes is the sa-me for all the 9o others which the machine may comprise, and is as follows:

The valve d in pipe D is closed, and the valve c in pipe O opened; the valve c in pipe C' closed, and valve i in pipe I opened. The 95 valves e and e', or either of them, in pipe E and the valves e2 and e3 in pipe F closed, the liquefied gas will flow from the condenser through pipes F, E', I, and C to the stack A, and, flowing upward, circulate in said stack, in the meantime rapidly expanding and lowering the temperature of the freezing-plates, passing oft' through pipe C to the pipe K, through which it goes back to the condenser. After being allowed to flow in this direction through the stack for a while, the valves which were closed are opened and those which were opened are closed, and the liquefied gas will now flow through the pipes E, D, and G to the top of the stack and downward through the same, -passing oft' through the pipes C' and K to pipe L, and back to the condenser, the reversal of flow through the stack being repeated as often as necessary and effecting a uniform cooling of the plates from top to bottom.

After the ice is formed, and it is desired to remove the same, the valve d, in pipeD, if before open, is closed, the valve g, in pipe Gr, opened, and weak water of ammonia flows through pipes H and G and C, and passing downward through the stack raises its temperature and that of the plates sufficiently to thaw loose the ice-blocks. The weak water passes off through pipeG, and as it enters the pipe K meets and absorbs, owing to its over coldness, a portion of the gas flowing through said pipe from other stacks, thus facilitating the subsequent process of absorption, as before explained.

Having now I claim is- 1. rIhe process of cooling uniformlyr thefreezingplates of an ice-machine, as herein described, the same consisting in causing the flow of refrigeratin g material which cools said lbeing now opened,

described my invention, what plates to be alternately in opposite directions, substantially as described.

2. The combination, with the freezing-plates of an ice-machine and a stack of circulatingpipes arranged between the same, of suitable connecting-pipes leading from opposite terminals ofsaid stack and connected with a liqueied-gas-supply pipe and a gas-return pipe, and provided with suitable valves and connections by which the refrigerating material may be caused to ow in alternate directions through said stack, substantially as and for the purpose set forth.

3. The combination,with the stack A, of the pipes C and G, gas-return pipes K and K', gas-supply pipes E and E and F, the connecting-pipes D and I, and suitable valves for controlling the flow through said pipes and connections, substantially as and for the purpose set forth.

4. The method of thawing off the ice from the ice-plates by causing a flow of weak water of ammonia through the stack of pipes, which serves to warm said plates, substantially as described.

5. The combination,in an ice-machine, with a circulating stack of pipes and a pipe for conducting the refrigeratin g material to said stack, of a pipe leading from said conducting-pipe and arranged for connection to the reservoir of weak water of ammonia,and suitable valves for controlling the ow through said pipes respectively, as desired.

In testimony that I claim the foregoing as my own I afx my two witnesses.

THOMAS L. RANKIN.

Witnesses:

W. C. MGARTHUR, L. E. LocKE.

signature in presence of 

